The present invention relates generally to fuel supply systems, and more particularly to a fuel supply system for a watercraft and in particular, to a fuel tank having a plurality of sealed, rotatable connections formed through a single opening in the tank.
Present marine fuel storage and distribution systems typically include a fuel tank, a fuel conduit connected between an engine and the fuel tank, a pump for conveying fuel through the conduit, a priming pump, one or more filters for removing sediment and water from the fuel prior to its delivery to the engine, fill and vent tubes connected to the tank, a cap for the fill tube that may provide the venting function when installed, and instrumentation for providing a signal corresponding to the level of fuel within the tank. One or more of these components may be duplicated in watercraft having more than one engine, or for the purpose of improved capacity, flexibility or reliability.
It is known that each joint or connection in a fuel system is a point for potential leakage of liquid fuel and/or vapors. It is therefore desirable to minimize the number of connections within a fuel system. In particular, it is desirable to minimize the number of connection to a fuel tank, since the tank is an expensive component to fabricate and is often installed in a location that is not accessible for repair activities. Furthermore, since the tank provides the primary boundary for the containment of the fuel, it is desirable to make the tank as fail-safe as possible.
It is also known that the space requirements and layout of a fuel system are important parameters in the design of a watercraft. The location, number and capacity of fuel tanks and the layout of fuel and vent lines may not be known until the power unit(s) for the boat are selected. Accessibility for routine maintenance and servicing must also be considered when designing a marine craft fuel system.
Thus there is a particular need for a fuel system for a watercraft that provides a high degree of flexibility for the marine designer. Such a fuel system should minimize the number of connections, and in particular, should minimize the number of penetrations into the fuel tank.
Accordingly, a fuel storage and supply apparatus for a watercraft is described herein as including: a fuel tank having an opening formed therein; a housing sealingly attached to the fuel tank within the opening, the housing having an opening formed therethrough; a tube disposed through the housing opening and longitudinally rotatable therewithin; and a radial O-ring seal disposed between a wall of the opening and an outside surface of the tube.
The tube of the watercraft fuel storage and supply apparatus is further described as including: a groove formed in the outside diameter surface of the tube for receiving and retaining the radial O-ring seal; a flange formed on the outside surface of the tube, the flange having a diameter greater than the diameter of the housing opening and having a bottom surface disposed against a top surface of the housing; and a clamping plate removably attached to the housing and covering at least a portion of the flange for retaining the tube within the housing opening.
The watercraft fuel storage and supply apparatus may further include: a valve cavity formed within the housing and in fluid communication between the interior and exterior of the tank; a check valve disposed within the valve cavity; a fuel outlet nozzle rotatably disposed within the valve cavity; and a radial O-ring seal disposed between the fuel outlet nozzle and a wall of the valve cavity. The check valve may include: a plate disposed within the valve cavity and sealed thereto about its perimeter; a hole formed in the plate for the passage of fuel therethrough; and an elastomer attached to the plate and extending therefrom to cover the hole, the elastomer operable to bend to permit fuel to pass out of the tank through the hole, and operable to seal the hole in the event of the flow of fuel into the tank.